Who's speaker is in my SWR cabinet

[zirkmaster]

I've had this SWR Bassic 2-way single 15 for years. I recently realised it might not have the original driver.
From the magnet side, there is no marking. Just a flat silver back. The front has no SWR logo on the cone.
Also the paper is all black from the center out.

On the back of the magnet drilled into the plate, there are four machined thread bases, in a square pattern. Anyone know what was screwed into the plate?

[RickenBoogie]

A picture is worth a thousand or so words.

[zirkmaster]

Here ya go!

[zirkmaster]

Anyone know what those female threads on the back magnet plate do?

[meycom]

I have that exact same cab, so I'm interested to hear as well....

[Benton]

I have a SWR Big Bertha 215 and the speakers looked like Ev but after checking learned they were PAS.

[staindbass]

the threads are for the screws that hold the magnet to the frame. they go through the frame next to the voice coil, and into the magnet assembly. if you take out the speaker, there are codes of numbers and letters on the back and cone. we could find out if you post them. Vintage Guitars Info - dating vintage guitars, amps by date source code here is a link with quite a few codes and how to decipher them.